1. Field of the Invention
The present invention relates to a heat-developable image-pattern recording material and, more particularly, to a heat-developable image-pattern recording material remarkably improved in the developability thereof.
Herein, the heat-developable image-pattern recording materials mean recording materials in which a latent image-pattern formed by some process is amplified by a heat-development and an image-pattern is thus obtained, and more concretely, such heat-developable image-pattern recording materials are classified into two kinds according to the latent image-pattern forming methods, one is a heat-developable light-sensitive material, wherein a latent image-pattern is formed by making use of a silver halide and by applying light thereto, and another one is an electro thermo-recording material, wherein a latent image-pattern is formed by applying an electric charge thereto.
2. Description of the Prior Art
With reference to heat-developable light-sensitive materials, there are descriptions in, for example, Japanese patent examined publication Nos. 4921/1968 and 4924/1968, and the like, wherein the light-sensitive materials comprising an organic silver salt, silver halide and reducing agent are disclosed. These heat-developable light-sensitive materials are to obtain silver image-patterns in the so-called dry physical development process that a latent image-pattern is formed on silver halide by exposing to light, and making the latent image-pattern serve as the catalytic nuclei, an oxidation-reduction reaction is performed with an organic silver salt and a reducing agent when the light-sensitive material is heated.
With reference to electro thermo-recording materials, there are descriptions in, for example, Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) Nos. 63621/1976, 23635/1978, 133041/1978, 144753/1978, 101333/1979 and 106229/1979, and the like, wherein the electro thermo-image-pattern recording materials comprising an organic silver salt and a reducing agent are disclosed.
In general, image-pattern forming compositions to be used in the abovementioned heat-developable image-pattern materials fundamentally comprise an organic silver salt and a reducing agent, and in addition thereto, a development accelerator and a color toning agent may be added thereto with the purposes of making developments accelerate to obtain an image-pattern having a relatively higher maximum density and an excellent tone, that has been well known.
As for the development accelerators and the color toning agents, there are described in, for example, Japanese Patent O.P.I. Publication Nos. 4928/1971, 6077/1971, 5019/1974, 5020/1974, 91215/1974, 107727/1974, 2524/1975, 67132/1975, 67641/1974, 114217/1975, 33722/1977, 99813/1977, 1020/1978, 55115/1978, 76020/1978, 125014/1978, 156523/1979, 156524/1979, 15625/1979, 156526/1979, 4060/1980, 4061/1980, and 32015/1980; W. German Pat. Nos. 2,140,406, 2,147,063, and 2,220,618; and U.S. Pat. Nos. 3,080,254, 3,847,612, 3,782,941, 3,994,732, 4,123,282 and 4,201,582; and the like; wherein the following compounds are given as the examples thereof: derivatives each of a phthalimide, pyrazolone, quinazolinone, N-hydroxynaphthalimide, benzoxadine, naphthoxadinedione, 2,3-dihydrophthaladinedione, 2,3-dihydro-1,3-oxadine-2,4-dione, oxypyridine, aminopyridine, hydroxyquinoline, aminoquinoline, isocarbostyryl, sulfonamide, 2H-1,3-benzothiazine-2,4-(3H)dione, benzotriazine, mercaptotriazole, dimercaptotetrazapentalene, phthalic acid, phtalazine, naphthalic acid, phthalamic acid, phthaladinone, and the like. Some of these compounds mostly increase fog at the same time when a development is effectively accelerated, though, and some of them mostly deteriorate the preservation stability of a heat-developable image-pattern recording material, before and after the development thereof is processed. Therefore, the compounds having a satisfactory performance has not yet obtained.